[Intel-gfx] [PATCH 1/8] drm/i915/dsi: defend gpio table against out of bounds access

[Jani Nikula]

Do not blindly trust the VBT data used for indexing.

Cc: stable at vger.kernel.org
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 drivers/gpu/drm/i915/intel_dsi_panel_vbt.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
index 1d43e6f37fc1..4775aa5462e8 100644
--- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
+++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
@@ -209,6 +209,11 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
 	/* pull up/down */
 	action = *data++;
 
+	if (gpio >= ARRAY_SIZE(gtable)) {
+		DRM_DEBUG_KMS("unknown gpio %u\n", gpio);
+		goto out;
+	}
+
 	function = gtable[gpio].function_reg;
 	pad = gtable[gpio].pad_reg;
 
@@ -226,6 +231,7 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
 	vlv_gpio_nc_write(dev_priv, pad, val);
 	mutex_unlock(&dev_priv->sb_lock);
 
+out:
 	return data;
 }
 
-- 
2.1.4